I am newbie at spring and generally webdev. I am writing small application in spring boot, where on hompage I display actual weatherstatus. Data is storage with help of JpaRepository and HSQLDB.
Each minute I recive data, parse, and add it to repository. The logic is done.
How to force client's browser to refresh, when I get new, actual Data?
With HTML:
To add this kind of feature without using any Ajax feature, you can use the following meta:
<meta http-equiv="refresh" content="0;URL='http://thetudors.example.com/'" />
https://www.w3.org/TR/WCAG20-TECHS/H76.html
With Javascript:
If you can add Javascript in the project, my advice is to create a endpoint to check periodically with JQuery or Fetch:
http://api.jquery.com/jquery.ajax/
https://www.npmjs.com/package/fetch
Juan Antonio
If you are using REST calls then it will be very easy for you.
<script>
$(document).ready(function(){
setInterval(getWeather(),2000);
//Here get weather is a method and 2000 is numbers of milliseconds after which you want to update weather data
});
function getWeather(){
$.ajax({
type : 'GET'
url : 'Your url here'
success : function(data){
//set received data to your container
}
});
}
</script>
Related
I am using ajax in html to load Json files to that the data will be refreshed every 5 seconds.
When I test it on my local host, everything works great. However, when I upload to google cloud Storage, it gives me some error shown as
Failed to load resource: the server responded with a status of 404 ()
GET https://00e9e64bac97921ce699e88ff28fbd14910d2de64676b68d82-apidata.googleus…/storage/v1/b/../o/TableGenerationData.json 400 ()
I put the json file in the same folder with the html, and my code is sure working,
<script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js"> </script>
<script type="text/javascript">
function refreshData()
{
var tt = $.ajax({
url: "TableGenerationData.json",
dataType: "json",
async: false
});
var jsonData = tt.responseJSON;
}
</script>
I couldn't get it working in google storage, does anyone have any idea?
Thank you very much.
Finally figured it out.
To make it work, I need to open the public link of the html file, and set the json file to be 'no-cache' to make sure new uploaded data will be immediately fetched by the html.
Thank you very much, welcome to make comment and share your idea if I am wrong.
I'm new to web development stuff and have been looking at some ember, I wanted to try running this with Spring boot. I got spring boot working and was able to run the sample blog example created with ember.
Now I want to some data read from the spring server, for example I can go to http://localhost:8080/greeting?name=User and get the following displayed onto the page
{"id":12,"content":"Hello, User!"}
What I want to do is get ember to read make that call instead of me manually adding it in the url and getting ember to then display that data.
So in ember my app.js looks like this
App.IndexRoute = Ember.Route.extend({
model: function() {
return $.getJSON("http://localhost:8080/greeting?name=User");
}
});
This I believe makes the call. I was trying to re-display the data onto the onto the index.html like this:
<script type="text/x-handlebars" data-template-name="index">
<Not sure what to put here>
</script>
I may be missing something obvious or not getting something. I apologize if thats the case. Any help will be welcome
The model hook in your route should resolve to {"id":12,"content":"Hello, User!"}. Once that is resolved, Ember will populate the model property of the corresponding controller (in this case, IndexController, which is auto-generated if you don't provide one).
As the index template you are using is backed by that controller, you can refer to any of its properties, including model:
<script type="text/x-handlebars" data-template-name="index">
{{model.content}}
</script>
I hope you can make it work!
I am fetching data from a URL using an AJAX call. It is giving a json object to me.
When I run the application, the page is working fine in IE with a conformation that
the page is accessing information that is not under its control.
This poses a security risk. Do you want to continue?
But that is not working in other browsers like Firefox, Chrome, Safari, etc.
i don't know what is the problem. Please explain to me why it is occurring and how to solve the issue?
My Code:
<!DOCTYPE html>
<html>
<head>
<title>Search Engine</title>
<script src="JS/jquery-1.4.2.min.js"></script>
<script>
$(document).ready(function () {
$.support.cors = true;
// create a script tag element
var script = document.createElement("script");
// set the attribute, using the URL to pass data via query parameters
script.setAttribute("src", "http://192.168.13.111:7090/?uname=bhagirathip&wt=json&fl=*,score");
script.setAttribute("type", "text/javascript");
// add the script tag to the document head, forcing an HTTP request
document.getElementsByTagName("head")[0].appendChild(script);
});
function Search() {
function callbackJsonHandler(data) {
alert(data); // This is the JSON data
}
}
</script>
</head>
<body>
<form id="form">
<div style="text-align: center">
<input type="search" id="searchInput" autofocus />
<input type="button" id="btnSearch" onclick="Search()" value="Search" />
</div>
</form>
</body>
</html>
You can't make cross-domain AJAX calls across domains. This is a security feature in web browsers to prevent malicious JavaScript code from scraping rendered data in a web page and then shipping it off to some rogue website on some other domain.
By restricting AJAX requests to same domain, browser vendors ensure that JavaScript imported from other sources cannot send data to any server other than the server the HTML page was served from.
In Internet Explorer, it's prompting you, but any smart user who encounters such a message is likely to say no. Presenting your users with such warning messages is not a good design practice and does not inspire confidence in the legitimacy of your application.
The only way that you can send data across domains is to use a browser hack technique called "script tag remoting", which essentially involves using HTML elements that aren't restricted by the same domain policy. For instance script tags can make HTTP GET requests to any server:
// create a script tag element
var script = document.createElement("script");
// set the attribute, using the URL to pass data via query parameters
script.setAttribute("src","http://192.168.9.11/userInput/?key="+userInput);
script.setAttribute("type","text/javascript");
// add the script tag to the document head, forcing an HTTP request
document.getElementsByTagName("head")[0].appendChild(script);
Using this method, you can send data to a remote server. Note that, to get JSON data back, you must wrap it, or pad it, in a JavaScript function and define a callback in the JavaScript code to handle the response:
function callbackJsonHandler(data) {
alert(data); // This is the JSON data
}
And your server-side code must return content text/javascript, calling the handler, and passing your JSON as an argument:
callbackJsonHandler({"key":"value","key1":"value2"});
When the browser downloads the JavaScript to the browser, the JavaScript runs immediately, giving you a hook to use to access the JSON in the response.
Since you're using jQuery, you can also check out jQuery JSONP, or JSON with Padding, which can be used to generate a JavaScript response so that you can handle callbacks from these requests to the remote server. Note that the server must be setup to handle JSONP requests for this to work properly, similar to the above setup.
Another solution to the issue of making cross-domain requests from a browser whose HTML document is served from exampleA.com to a server whose domain is exampleB.com is to use a proxy.
Let's assume that the HTML document you're working with is served from exampleA.com. You own exampleA.com, and you can access the server side and client side code. exampleB.com, on the other hand, is a remote server owned or controlled by someone else. exampleB.com has some data you want to use in exampleA.com.
We know that AJAX won't work, because of the same origin policy, which is in place to protect rogue apps from doing bad things with people's data. However, servers aren't restricted to same domain policy. This means that your app can do the following:
||exampleA.com/test.html|| ---> http req --> ||exampleA.com/getData|| --http req --> ||exampleB.com/getJSON||
Server-side: (As in your server, exampleA.com):
In other words, on your server that you're using to serve the HTML, you write some code that makes an HTTP request from your server to the third-party server:
// JSON URL which should be requested
$json_url = 'http://www.exampleB.com/getJSON';
// Initializing curl
$ch = curl_init( $json_url );
// Configuring curl options
$options = array(
CURLOPT_RETURNTRANSFER => true,
CURLOPT_HTTPHEADER => array('Content-type: application/json')
);
// Setting curl options
curl_setopt_array( $ch, $options );
// Getting results
$result = curl_exec($ch); // Getting JSON result string
See Getting JSON Data with PHP Curl for more details. Each server-side platform has the ability to make HTTP connections to servers.
// now, send the data in the response
HttpResponse::status(200);
HttpResponse::setContentType('application/json');
HttpResponse::setData($result);
HttpResponse::send();
See PHP HTTPResponse. Again, whatever language you're working with should have the ability to return data from a string.
Put the above code in a file called "getJSON.php", assuming you're using PHP. Make sure there is no whitespace between the opening <?php and the beginning of the document; otherwise, you will not be able to set the headers. There is likely a better way to send this response, but since your platform isn't specified, I'll leave that as an exercise for the reader.
Client-side code:
var searchURL = "/getJSON.php"; //From this URL json formatted data is present.
$.ajax({
url: searchURL,
type: 'GET',
dataType: 'json',
contentType: 'application/json; charset=utf-8',
success: function (data) {
try {
alert(data);
}
catch (err) {
alert(err);
}
}
});
Now, in the above JavaScript code, you make a same-domain AJAX request to your server exampleA.com, and then your server makes a request on your behalf to exampleB.com to get the data, then exampleA.com returns the data in the response to the browser.
My application is located on the server under a separate virtual directory. To access my ASP.NET MVC application users have to go to:
http://server-dev/superApp
I have a problem with Ajax/Json server requests ignoring the "superApp" directory part. Whenever an Ajax request is made Fiddler shows 404 because instead of http://server-dev/superApp/User/GetUsersJson for example, http://server-dev/User/GetUsersJson is called (note the missing superApp name).
Example of an Ajax request:
function GetUsers(id) {
$.ajax({
url: "/User/GetUsersJson/",
data:{ id: id},
datatype: 'json',
type:'post',
success: function (result) {
////Do stuff with returned result
}
});
}
Registered route:
r.Match("User/GetUsersJson", "User", "GetUsersJson");
Where should I look and what can I change to make sure that my application virtual folder is ALWAYS included in all URL requests ?
p.s. Please note that all Javascript/Ajax logic is kept in separate .js files so no RAZOR syntax is available.
Did you try using the HTML helper method ?
url: "#Url.ACtion("GetUsersJson","User)"
EDIT : As per the comment
You may get the Path name using the HTML Helper method and Keep that in a Global variable and access that in the external javascript file
In the view
<script type="text/javascript>
var globalGetJSONPath='#Url.ACtion("GetUsersJson","User)';
</script>
And now you can use it in the external file like this
$.ajax({
url: globalGetJSONPath,
data:{ id: id},
//remaining items....
});
I solved this stuff by passing variable to js that contains hostname+vdir. Because of heavy js url generation.
In other cases Shyju's answer is best way to solve this.
No way to do it without some server-side code generation. Easiest thing would be defining global variable (sorry) holding you application root and initializing it somewhere in master page.
Javascript generation of route urls always was one of the messiest parts of asp.net mvc.
I am trying to make a RESTful webservice call using Extjs. Below is the code i am using:
Ext.Ajax.request({ url: incomingURL ,
method: 'POST',
params: {param1:p1, param2:p2},
success: function(responseObject){
var obj = Ext.decode(responseObject.responseText);
alert(obj);
},
failure: function(responseObject){
var obj = Ext.decode(responseObject.responseText);
alert(obj);
}
});
but it does not work, the request is sent using OPTIONS method instead of POST.
I also tried to do the same thing using below code but result is the same:
var conn = new Ext.data.Connection();
conn.request({
url: incomingURL,
method: 'POST',
params: {param1:p1, param2:p2},
success: function(responseObject)
{
Ext.Msg.alert('Status', 'success');
},
failure: function(responseObject)
{
Ext.Msg.alert('Status', 'Failure');
}
});
But when i tried to do the same thing using basic ajax call ( using the browser objects directly i.e. XMLHttpRequest() or ActiveXObject("Microsoft.XMLHTTP")) it works fine and i get the response as expected.
Can anyone please help me, as i am not able to understand what i am doing wrong with extjs ajax call?
You can't make a standard AJAX call between domains. The URL for Ext.Ajax.request should be a relative one (relative to the script's origin).
If you want to do cross-domain calls, use a ScriptTagProxy or such.
The problem is exactly because of the reason ob1 and Chuck Hinson described.
I have an RESTful service, wich is running on Tomcat.
And i made a static client(no deployed to Tomcat) using ExtJs with Json reader.
I just made an html page with ExtJs integrated consuming REST service like url: http://localhost:8080/service/invoices/
And all the time ExtJs was making OPTIONS request, not GET or POST even if i was setting them as being used methods. The problem is this security feature, because Client is not the part of same application and i am doing AJAX call between domains.
As soon as i put my client to my Web application and deployed to Tomcat and started using relative calls it started working.
if you don't want cross-domain request, please remove the website prefix 'http://website' from propery url of ajax proxy.